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Date: Mon, 12 Mar 2012 20:46:30 +0000
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: ShuoX Liu <shuox.liu@intel.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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Subject: Re: [PATCH 2/3] cpuidle: Add a debugfs entry to disable specific C
 state for debug purpose.
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On Mon, Mar 12, 2012 at 05:21:33PM +0800, ShuoX Liu wrote:

> In addition, C state might have much impact on performance tuning,
> as it takes
> much time to enter/exit C states, which might delay interrupt
> processing. With
> the new debug option, developers could check if a deep C state could impact
> performance and how much impact it could cause.

Would anyone doing performance tuning not be using the cpu_dma_latency 
interface?

-- 
Matthew Garrett | mjg59@srcf.ucam.org